Sudden cardiac arrest resulting from heart attack, or cardiac arrest or ventricular fibrillation (VF), a spontaneous, mostly fatal interruption of normal heartbeat, is a leading cause of death. Survival rates for VF are about 5 to 10 percent.
Sometimes the stricken individual, or VF victim or “patient,” will be fortunate enough to suffer from VF in proximity to someone who has received cardiopulmonary resuscitation (CPR) training. Nonetheless, a large number of CPR-trained individuals are not able to provide effective emergency care when an individual has suffered from VF. In this regard, Brennan and Braslow found that 45% of 226 recent graduates of CPR training failed to open the airway prior to checking for respiration and that 50% of the recent graduates failed to adequately assess the patient's respiratory status. Failure in these critical CPR administration skills may contribute to poor survival rate following out-of-hospital VF.
Even when CPR has been properly administered to an individual who has suffered VF, survival rates decrease by about 10 percent for every minute that goes by without a stricken individual receiving a defibrillation shock. In the United States, it generally takes about six to twelve minutes for the average emergency medical services (EMS) team to arrive at the scene of a medical emergency.
Automatic external defibrillators (AED) can significantly increase successful outcomes following sudden cardiac arrest. Success rates rise from 3% to 70% when AEDs are used within 3-4 minutes of arrest, with recent studies showing that up to 70 percent of VF victims survive when AEDs are accessible. Clearly, early defibrillation is the key to saving lives.
Conventionally, use of AEDs to treat VF has been limited to caregivers with some level of medical expertise, including, without limitation, doctors, nurses, emergency medical technicians (EMTs), law enforcement personnel, fire personnel, security guards, health club employees, flight attendants, lifeguards, and office managers. The American Heart Association (AHA) estimates that, in the U.S., nearly 120,000 of the approximately 300,000 people who die annually from sudden cardiac arrest could be saved with public access defibrillation. According to the AHA, “Public access defibrillation, which places AEDs in the hands of trained laypersons, has the potential to be the single greatest advance in the treatment of VF cardiac arrest since the development of CPR.” Only recently, however, have public access AEDs become available.
In view of the foregoing, the federal government of the U.S. has taken several measures to reduce the incidence of deaths that are attributable to out-of-hospital occurrences of VF. For example, the U.S. Occupational Safety and Health Administration (OSHA) has endorsed the placement of AEDs in the workplace, the U.S. Congress has passed the Community Access to Early Defibrillation Act to provide funds for the purchase of defibrillators, and the U.S. Congress has enacted the 1999 Cardiac Arrest Survival Act, which mandates placement of defibrillators in all federal buildings.
Although efforts are being made to place AEDs in a variety of locations, currently available AEDs are difficult for untrained or minimally trained individuals to use. For example, members of the flight crew on the International Space Station (ISS) are only required to have 40 hours of emergency medical training. Upon discovering a “patient in distress,” two members of the flight crew onboard the ISS are responsible for stabilizing the injured crew member until support can be provided by ground-based flight surgeons. When the ISS is not in communication with ground-based support (the link with ground-based flight surgeons is only useful about half of the time and is subject to blackout periods that last for about ten or fifteen minutes), the crew is trained to use the Integrated Medical Group (IMG) Medical Checklist and follow a twenty-four page Advanced Cardiac Life Support algorithm. This is a formidable task for crewmembers with only 40 hours of medical training.
Recent studies indicate that the treatment of a VF victim following the current National Aeronautics and Space Administration (NASA) protocol would take too long, primarily due to the lengthy text-based instructions and difficulty in understanding such instructions in a high-stress situation.
Accordingly, there is a need for apparatus, systems, and methods for providing responders, including untrained and minimally trained individuals, with emergency medical care instructions, including, but not limited to, administration of CPR and effective use of AED, in real time.